Charging device that reduces an amount of noise flowing through a quick charging system in a vehicle

ABSTRACT

Provided are a charging device and a vehicle capable of reducing the amount of noise flowing into a quick-charging facility. The pair of charging lines connecting the quick-charging facility ( 20 ) to an onboard battery ( 30 ) are referred to as quick-charging lines, and each of these quick-charging lines is provided with a relay ( 16 - 1, 16 - 2 ). Each relay ( 16 - 1, 16 - 2 ) is used to switch the current flowing in the respective quick-charging line on and off, the current being switched on during quick-charge and being switched off during normal charging. Each quick-charging line has a Y-capacitor ( 17 ) connected thereto closer to a QC port ( 15 ) than the respective relay ( 16 - 1, 16 - 2 ).

TECHNICAL FIELD

The present invention relates to an onboard charging apparatus and avehicle that are quickly charged by a quick-charging system providedoutside a vehicle.

BACKGROUND ART

Recently, automobiles that run on electricity, such as an ElectricVehicle (EV), and a Plug-in Hybrid Electric Vehicle (PHEV) (hereinafter,referred to simply as “vehicles”) have gradually become popular. Suchvehicles are equipped with a large-capacity storage battery, and storein the storage battery electric energy charged from the outside and runusing the stored electric energy

As a method for supplying electric power to a vehicle storage batteryfrom the outside, a method is available in which a charger installed ina vehicle receives the supply of alternating-current (AC) power from a100V AC power source used in ordinary households and converts the ACpower to direct-current (DC) power to charge a storage battery. Thismethod requires a noise-eliminating device for eliminating noise, inorder to prevent the inflow of noise into the AC power source. Acharging apparatus having such a noise-eliminating device is disclosed,for example, in Patent Literature (hereinafter, referred to as “PTL”) 1.

PTL 1 discloses a charging apparatus including a switch in anintermediate grounding conductor that connects, to the ground, a groundside terminal of a Y capacitor that eliminates noise. The switch isconfigured to connect and disconnect the intermediate groundingconductor, and the charging apparatus disconnects the intermediategrounding conductor by controlling the switch when a security groundterminal is not connected to the ground. Thus, this switching preventsthe occurrence of a large potential difference between a vehicle bodyand the ground even when the intermediate ground conductor is notconnected to the ground sufficiently.

Meanwhile, as a method for supplying electric power to a vehicle storagebattery from the outside, another method is available in which aquick-charging system provided outside a vehicle directly supplies largeDC power to a storage battery.

CITATION LIST Patent Literature

PTL 1

Japanese Patent Application Laid-Open No. 2009-240016

SUMMARY OF INVENTION Technical Problem

However, the quick-charging line that connects the quick-charging systemto the storage battery is not provided with a noise countermeasure.Therefore, there is a problem in which, when a circuit such as a DC/DCconverter that operates using the storage battery as a power sourceundesirably starts operating during quick charging, noise may occur fromsuch a circuit and flow into the quick-charging system.

An object of the present invention is to provide a charging apparatusand a vehicle each reducing the amount of noise flowing into aquick-charging system.

Solution to Problem

The charging apparatus of the present invention has a configurationincluding: a quick-charging line having one end being connected to aline between a battery and a component which becomes a noise source whenthe component operates during quick charging to the battery, and havingthe other end being connected to an input side of quick charging; and afirst noise filter that is disposed on the quick-charging line andeliminates noise.

Advantageous Effects of Invention

According to the present invention, it is possible to reduce the amountof noise flowing into a quick-charging system.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a configuration of a charging apparatusaccording to an embodiment of the present invention.

DESCRIPTION OF EMBODIMENT

Hereinafter, an embodiment of the present invention will be described indetail with reference to the drawing.

Embodiment

<Configuration of Charging Apparatus>

FIG. 1 is a diagram illustrating a configuration of charging apparatus 1according to an embodiment of the present invention. Hereinafter, theconfiguration of charging apparatus 1 will be described with the aid ofFIG. 1. FIG. 1 also illustrates, in addition to charging apparatus 1,100 V AC power source 10 used in ordinary households, quick-chargingsystem 20 that is provided outside a vehicle and supplies large DC power(e.g., 300 V), and onboard battery 30 that is a storage battery such asa lithium-ion battery. Charging apparatus 1 is equipped on vehicles suchas an EV having onboard battery 30, and charges onboard battery 30utilizing power from AC power source 10 or quick-charging system 20.

AC/DC converter 13 including bridge circuit 11, transformer 12, and aswitching circuit (not illustrated) or the like converts AC powersupplied from AC power source 10 to DC power, and onboard battery 30 ischarged.

A pair of charging lines connecting AC power source 10 to bridge circuit11 is referred to as normal charging lines, and Y capacitors 14 areconnected to the normal charging lines, respectively. Y capacitors 14are grounded to the body ground at a neutral point and reduce noise thatflows into AC power source 10 from AC/DC converter 13 to a certaincurrent value or lower and causes the noise to flow to the body ground.

QC port 15 is a connector capable of detachably connectingquick-charging system 20 to charging apparatus 1.

A pair of charging lines each having one end being connected to a linethat connects onboard battery 30 to DC/DC converter 18, and airconditioning compressor 19, and/or the like to be described hereinafter,and the other end being connected to QC port 15 is referred to as aquick-charging line, and the respective quick-charging lines areprovided with relays 16-1 and 16-2. Relays 16-1 and 16-2 switch on andoff the current flowing through the quick-charging line. Relays 16-1 and16-2 switch the current on during quick charging, and switch the currentoff during normal charging.

Further, Y capacitors 17 are connected respectively to thequick-charging lines on QC port 15 side (input side of quick charging)with respect to relays 16-1 and 16-2 of the respective quick-charginglines. Y capacitor 17 is connected to the body ground at a neutral pointand reduces noise from DC/DC converter 18 and air-conditioningcompressor 19 to be described hereinafter to a certain current value orlower and causes the noise to flow to the body ground.

DC/DC converter 18 lowers DC power supplied from onboard battery 30 toabout 14 V, for example, and supplies the power to electric componentsof the vehicle. Further, air-conditioning compressor 19 uses the DCpower supplied from onboard battery 30 to compress a refrigerant for airconditioning. It is noted that DC/DC converter 18 and air-conditioningcompressor 19 become a noise source that generates noise, when theyoperate during quick charging.

Onboard battery 30 is charged by AC power source 10 or quick-chargingsystem 20, and supplies the charged power to DC/DC converter 18,air-conditioning compressor 19, and an inverter (not illustrated) or thelike.

In this manner, charging apparatus 1 connects Y capacitors 17 to thequick-charging lines. Thus, even when DC/DC converter 18, andair-conditioning compressor 19, and/or the like operate during quickcharging, the amount of noise flowing into quick-charging system 20 canbe reduced by causing the noise generated from these circuits to flow tothe body ground through Y capacitor s.

<Y capacitors for Quick Charging>

Here, Y capacitors 17 will be described.

When Y capacitors 17 are provided on onboard battery 30 side withrespect to relays 16-1 and 16-2, the total electrostatic capacitance ofY capacitors 17 and Y capacitors 14 for normal charging increases, whichcauses a current flowing through the vehicle body to increase duringnormal charging, thus undesirably increasing the possibility of anelectric shock.

Under such circumstances, the present invention provides Y capacitors 17on QC port 15 side with respect to relays 16-1 and 16-2 of thequick-charging lines, as described above, to thereby prevent the inflowof noise into Y capacitors 17 during normal charging. Thus, it becomespossible to avoid the increase of the total electrostatic capacitance ofthe Y capacitors, thereby avoiding the possibility of an electric shock.

It is noted that, since transformer 12 is isolated during quickcharging, no noise flows into Y capacitors 14. Further, there is astandard which requires that a leakage current from a Y capacitor shouldbe 3.5 mA or lower (IEC 61851), and thus, the electrostatic capacitanceof a Y capacitor needs to be 35.16 nF or lower due to this requirement.

Effects of Embodiment

Thus, according to the present embodiment, connecting Y capacitors 17 tothe quick-charging lines that connects quick-charging system 20 toonboard battery 30 makes it possible to reduce the amount of noiseflowing into quick-charging system 20 by causing the noise generatedfrom noise sources such as DC/DC converter 18, and air-conditioningcompressor 19 and/or the like to flow to the body ground through Ycapacitors 17, even when these noise sources operate during quickcharging.

Further, according to the present embodiment, disposing Y capacitors 17on QC port 15 side with respect to relays 16-1 and 16-2 of thequick-charging lines makes it possible to block the noise from flowinginto Y capacitors 17 during normal charging, thus avoiding the increaseof the total electrostatic capacitance of the Y capacitors, to therebyavoid the possibility of an electric shock.

Note that, the description has been given with the Y capacitors eachserving as a capacitor to be connected to the quick-charging line in thepresent embodiment, but an X capacitor, a coil, a ferrite, or the likemay be used in place of the Y capacitor as a countermeasure againstnoise. Further, the number of Y capacitors to be connected to thequick-charging lines may be one.

In addition, the present embodiment has been described with theassumption that DC/DC converter 18 and air-conditioning compressor 19which become noise sources that generate noise when they operate duringquick charging are also included in charging apparatus 1, but thesenoise sources need not be included in charging apparatus 1.

The disclosure of Japanese Patent Application No. 2013-122988, filed onJun. 11, 2013, including the specification, drawing and abstract, isincorporated herein by reference in its entirety.

INDUSTRIAL APPLICABILITY

The charging apparatus and vehicle according to the present inventionare applicable to automobiles that run on electricity, such as an EV anda PHEV.

REFERENCE SIGNS LIST

1 Charging apparatus

10 AC power source

11 Bridge circuit

12 Transformer

13 AC/DC converter

14, 17 Y capacitor

15 QC port

16-1, 16-2 Relay

18 DC/DC converter

19 Air-conditioning compressor

20 Quick-charging system

30 Onboard battery

The invention claimed is:
 1. A charging apparatus comprising: aquick-charging line for supplying direct-current power supplied from anexternal direct-current power source to a battery, the quick-chargingline having one end being connected to a line between a battery and acomponent which becomes a noise source when the component operatesduring quick charging to the battery, and having the other end beingconnected to an input side of quick charging, a first noise filter thatis disposed on the quick-charging line and eliminates noise, an AC/DCconverter having a transformer, the AC/DC converter convertingalternating-current power supplied from an external alternating-currentpower source to direct-current power and supplying the power to thebattery; and a second noise filter that is disposed on a normal chargingline connecting the external alternating-current power source to theAC/DC converter and eliminates noise.
 2. The charging apparatusaccording to claim 1, further comprising: a relay that is disposed onthe quick-charging line and switches on and off a current flowingthrough the quick-charging line, wherein the first noise filter isdisposed on the input side of quick charging with respect to the relay.3. The charging apparatus according to claim 1, wherein each of thefirst noise filter and the second noise filter is a Y capacitor.
 4. Thecharging apparatus according to claim 3, wherein the relay is switchedon during quick charging, and is switched off during normal charging. 5.A vehicle comprising: a battery; and a quick-charging line for supplyingdirect-current power supplied from an outside of a vehicle to thebattery, the quick-charging line having one end being connected to aline between a battery and a component which becomes a noise source whenthe component operates during quick charging to the battery, and havingthe other end being connected to an input side of quick charging, afirst noise filter that is disposed on the quick-charging line andeliminates noise, an AC/DC converter having a transformer, the AC/DCconverter converting alternating-current power supplied from an externalalternating-current power source to direct-current power and supplyingthe power to the battery; and a second noise filter that is disposed ona normal charging line connecting the external alternating-current powersource to the AC/DC converter and eliminates noise.
 6. The vehicleaccording to claim 5, further comprising: a relay that is disposed onthe quick-charging line and switches on and off a current flowingthrough the quick-charging line, wherein the first noise filter isdisposed on the input side of quick charging with respect to the relay.7. The charging apparatus according to claim 1, wherein the first noisefilter eliminates noise from a plurality of components which become anoise source.
 8. The charging apparatus according to claim 7, whereinthe first noise filter is disposed outside the plurality of components.